Rotary type sweeper

ABSTRACT

A rotary type sweeper has a housing body within which is mounted a first or conventional roller brush which is rotatable in engagement with the surface to be cleaned when the sweeper is moved forwardly and backwardly. Dust collecting compartments are disposed to the front and rear of the first roller brush, and a second roller brush is rotatably mounted within the housing body and to the front or rear of the first brush roller. The second roller brush has short bristles closely implanted on the surface and inclined in one and the same direction along the circumference of the second roller brush. A first dust removing member which has short bristles closely implanted on the surface and inclined in one and the same direction is movably mounted in engagement with the second roller brush, and a second dust removing member which is stationary and has short bristles closely implanted on the surface and inclined in one and the same direction is engaged by the bristles on the first dust removing member. All the bristles on the second roller brush, first dust removing member and second dust removing member are inclined in the same direction.

Uiteol States Tsuruzawa et al.

[ ROTARY TYPE SWEEIPER [75] lnventors: T'eruya Tsuruzawa; lsamu Uhta,

both of Suita; Muneyultl Ueda, Nishinomiya; lKazuyulti Shimizu, Osaka, all of Japan [73] Assignee: Nippon Seal (10., Ltd., Osaka, Japan [22] Filed: May 2, 1973 [21] Appl No.: 356,446

[30] Foreign Application Priority Data May 2, 1972 Japan 47-43873 [52] 11.8. CI. 15/48 [51] Int. Cl A471 11/32 [58] Field 01' Search 15/42, 48, 41 R [5.6] References Cited UNITED STATES PATENTS $587,127 6/1971 Rosendall 15/48 3,747,152 7/1973 Tsuruzawa 15/48 X FOREIGN PATENTS OR APPLICATIONS l,934,025 1/1971 Germany 15/48 2,060,377 6/1971 Germany 15/48 Primary Examiner--Edward L. Roberts Attorney, Agent, or Firm-Wenderoth, Lind & Ponack [5 7 1 ABSTRACT A rotary type sweeper has a housing body within which is mounted a first or conventional roller brush which is rotatable in engagement with the surface to be cleaned when the sweeper is moved forwardly and backwardly. Dust collecting compartments are disposed to the front and rear of the first roller brush, and a second roller brush is rotatably mounted within the housing body and to the front or rear of the first brush roller. The second roller brush has short bristles closely implanted on the surface and inclined in one and the same direction along the circumference of the second roller brush. A first dust removing member which has short bristles closely implanted on the surface and inclined in one and the same direction is movably mounted in engagement with the second roller brush, and a second dust removing member which is stationary and has short bristles closely implanted on the surface and inclined in one and the same direc tion is engaged by the bristles on the first dust removin}; member. All the bristles on the second roller brush, first dust removing member and second dust removing member are inclined in the same direction.

5 Claims, 4 Drawing Figures Various kinds of rotary type carpet sweepers which are manually operated are well known. In conventional rotary type carpet sweepers, there is provided only a roller brush having bistles extending radially of its rotary shaft. Therefore it is difficult to clean the pile or up relatively coarse dust or the like but not fluff, lint, fine dust or the like which may also be adhered to the carpet. In order to overcome this drawback and to ren textile structure of fluff, lint or the like adhered thereto or of relatively fine'dust, although the conventional brush may be able to remove somewhat coarse dusts.

Therefore it is an object of this invention to provide an improved rotary type sweeper with a new and special roller brush for effectively removing fluff, lint, fine dust and the like from carpets, floor coverings, upholstery or the like.

Another object of this invention is to provide an improved rotary type sweeper having means for automatically removing fluff, lint, dust and the like from the roller brush and for collecting them.

Other objects of this invention will become apparent from the following description.

Briefly, the rotary type sweeper according to this invention comprises a housing body within which is mounted a first or conventional roller brush rotatable in engagement with the surface to be cleaned when the sweeper is moved back and forth, dust collecting compartments disposed in front of and to the rear of the front roller brush, a second roller brush which is rotatably mounted within the housing body and in front of or to the rear of the first brush roller and which has short bristles closely implanted at an angle on the surface which lean in the same direction along the entire circumference. A first dust removing member which has short bristles closely implanted at an angle on the surface and which are inclined in same direction and which is movable in engagement with the second roller brush is provided together with a second dust removing member which is stationary and has short bristles closely implanted at an angle on the surface and which are inclined in the same direction, the bristles on the first dust removing member being engageable with the bristles on the second or stationary dust removing member when the first dust removing member is moved, all the bristles on the second roller brush, first dust removing member and second dust removing member being inclined in the same direction.

The first roller brush may be any conventional one which is rotatable in engagement with the surface to be cleaned when the sweeper is moved back and forth. For example, it may be of the type wherein bristles are closely implanted on the whole surface or of the type wherein bristles are arranged spirally along the axis. In any case the bristles extend substantially radially of the rotary shaft so that when the roller brush is rotated in engagement with the surface to be cleaned, relatively coarse dust on the surface (e.g. carpet) is taken up by the bristles and thrown into the dust collecting compartments arranged in front of and to the rear of the first roller brush. This type of roller brush is well known per se and therefore no further detailed explanation thereabout will be required.

As pointed out hereinbefore the drawback of such conventional or first roller brush is that it can only take der the rotary type sweeper efficient to the greatest possible extent there is provided, according to this invention, a special or second roller brush in addition to the conventional or first roller brush mentioned above. Thus the provision of second roller brush with very special structural feature is the novel and important fea-' ture of this invention. 7

Thus the second roller brush is rotatably mounted within the same housing body and in fact of or to the rear of the first roller brush. The second roller brush is also engageable with the surface to be cleaned. The

most important feature of the second roller brush is.

that it has numerous bristles closely implanted on the roller surface and inclined in the same direction along the entire circumference.

Within the housing body is a first dust removing member which has numerous short bristles closely implanted on the surface and inclined in the same direction. The first dust removing member is movable (slidable or swingable) in engagement with the second roller brush but its movement is limited by a proper stopper means. i

There is further provided a second dust removing member which is stationary andwhich has numerous short bristles closely implanted on the surface and in clined in the same direction. The bristles on the first dust removing member are engageable with the bristles on the second dust removing member when the first dust removing member is moved. The second dust removing member is arranged adjacent to and above the dust collecting compartment.

All of the bristles on the second roller brush, first dust removing member and second dust removing member are inclined in the same direction.

Preferably the bristles on the second roller brush, first and second dust removing members have a length of 2 7 mm. and are inclined at an angle of between 10 If desired, another set of the second roller brush, first and second dust removing members may be provided symmetrically in respect of the first set, and the first roller brush is then arranged between the first and the second set. In this case it ispreferable that the bristles on the first set are inclined in a direction opposite to that of the bristles on the second set.

Each of the dust collecting compartments may be provided with a suitable means for removing the dust collected therein.

There may be provided a handle on the sweeper body for manually moving the sweeper on the surface to be cleaned.

The rotary type sweeper having the above mentioned structure and arrangement according to this invention works as follows, assuming that the bristles on the second roller brush are inclined in the counter-clockwise direction as seen from one side. When the sweeper is moved forwardly or backwardly the first roller brush is rotated, relatively coarse dust and the like on the surface to be cleaned are picked up by the bristles on the first roller brush and are thrown into the dust collecting compartment. This workingis conventional one and well known in the art.

When the sweeper is first moved forwardly or in the direction opposite to the inclination of the bristles on the second roller brush as seen at the contact or enroller brush will rotate due to contact with the surface to be cleaned but at a reduced speed due to engagement with the first dust removing member while pushing the latter forwardly or in the direction of the movement of the sweeper until it is stopped by means of a stopper. Since the bristles on the second roller brush are inclined in a direction opposite to the movement of the sweeper the bristles on the second roller brush will slide on the surface being cleaned and do not perform a cleaning function. Thus during the first forward movement of the sweeper only the first roller brush performs the cleaning function.

Then the sweeper is moved backwardly or in the direction opposite to the above mentioned first forward movement, the second roller brush rotates in the direction opposite to the movement of the sweeper due to the positive engagement of the bristles on the second roller brush with the surface to be cleaned. In other words, in this first backward movement of the sweeper, the second roller brush rotates in a direction opposite to that in the case of the first forward movement of the sweeper. However here again the speed of rotation of the second roller brushis reduced due to the engagement with the first dust removing chamber while pushing the latter backwardly or to the direction of the movement of the sweeper until it is stopped by means of another stopper. During the rotation the inclined bristles on the second roller brush engage the surface (e.g. carpet) to be cleaned and the fluff, lint, fine dust or the like which have not been removed by the. first roller brush are swept off and taken up by the bristles of the second roller brush. As the second roller brush further rotates, the fluff, lint, fine dust or the like retained by the inclined bristles on the second roller brush are removed and transferred into the bristles on the first dust removing member. Thus the second roller brush is cleaned by the first dust removing member and is rendered ready for the subsequent brushing or sweeping operation.

When the sweeper is again moved forwardly (this movement may be referred to as second forward movement) the second roller brush and the first dust removing member are moved in the same manner as explained in the first forward movement of thesweeper. Thus the second roller brush does not perform the cleaning while simply slipping on the surface to be cleaned. In this case, again, the first dust removing member is pushed forwardly due to the engagement with the rotating second roller brush. During this forward movement the first dust removing member engages the second dust removing member. However, since the inclination of the bristles on the first dust removing member is the same as that of the bristles on the second dust removing member which is stationary (as explained before), the dust or the like now accumulated in the bristles of the first dust removing member remain therein without being removed by the bristles on the second dust removing member even when these two dust removing members engage with each other during the second forward movement of the sweeper.

Then the sweeper is again moved backwardly. This backward movement may be referred to as the second backward movement of the sweeper. During this second backward movement of the sweeper the second roller brush and first dust removing member are moved in the same manner as explained above in the description of first backward movement of the sweeper. Thus the second roller brush performs the cleaning of the surface to be cleaned, and the first dust removing member is moved backwardly until it is stopped by a stopper means. Even after the stoppage of the first dust removing member the second roller brush engages therewith during its rotation and the dust or the like among the bristles on the second roller brush is transferred into the bristles on the first dust removing member. During the above mentioned backward movement the bristles on the first dust removing member engage with the bristles on the stationary second dust removing member so that the dust or the like already retainedamong the bristles on the first dust removing member is combed off by and transferred into the bristles on the second dust removing member.

It will be understood therefore that the first dust removing member moves toward or away from the second or stationary dustremoving member depending upon the direction of rotation of the second roller brush with which the first dust removing member is engaged.

The dust or the like retained in the second dust removing member is pushed forwardly by the bristles on the first dust removing member at the time of the subsequent forward movement of the first dust removing member, and ultimately out of the second dust removing member into the dust collecting compartment.

With the repetition of such operation (i.e. first forward movement, first backward movement, second forward movement and second forward movement of the sweeper in the mentioned order), the coarse dust and the like is taken-up by the conventional first roller brush, while fluff, lint, fine dust and the like is taken-up by the second roller brush, transferred to the first dust removing member and then to the second dust removing member and ultimately discharged into the dust collecting compartment. The dust and the like accumulated in the dust collecting compartment may be disposed of by any suitable manner.

If desired, the direction of inclination of the bristles on the second roller brush (and hence the direction of the inclination of the bristles on the first and second dust removing members) may be made opposite to that explained hereinabove. In this case, it will be understood that the second roller brush will perform the cleaning only in the forward movement of the sweeper.

Further it is possible to shift the position of the operation handle so that the above mentioned forward movement and backward movement of the sweeper becomes backward movement and forward movement respectively. In the latter case it will be understood that the second roller brush will perform the cleaning only in the forward movement of the sweeper.

As mentioned before it is also possible to provide two sets of the second roller brush and associated members (first and second dust removing members), the first roller brush being positioned between these two sets. In this case it is preferable that the direction of inclination of the bristles on the one set is opposite to that of the bristles on the other set, so that when the sweeper is moved in any direction (forward or backward) one of the two sets performs the cleaning operation.

The invention will be further explained by referring to the accompanying drawings wherein:

FIG. 1 is a vertical sectional view of a rotary type sweeper embodying the present invention,

FIG. 2 is a vertical section of another embodiment of this invention,

FIG. 3 is a schematic perspective view, partly broken, of the sweeper shown in FIG. 1, and

FIG. 4 is a vertical section of the main portion of a still modified embodiment of the invention.

Referring to FIGS. 1 and 3, drive wheels 1 and 1' to be driven (due to engagement with the surface, e.g., carpet to be cleaned) by the forward and backward travel of a housing or main body A are rotatably supported by shafts 2 and 2' respectively on an outer frame a of a main body cover 18. Disposed between and in contact with the drive wheels 1 and 1' is a driven wheel 3 rotatably supported on the outer frame a by a shaft 4, which fixedly carries a conventional roller brush (first roller brush) 5 formed with radially extending bristles 6. Dust collecting compartments I9 and 19 are provided in front of and to the rear of the first roller brush 5 and in proximity thereto. The above mentioned is a construction of a typical conventional rotary type carpet sweeper.

A second roller brush 7 having numerous bristles 8 closely positioned on its outer peripheral surface and inclined in the same direction (counter-clockwise direction in the embodiment shown) is rotatably supported by a shaft 9 on an inner frame c. In contact with the upper portion of the second roller brush 7, there is provided a first dust removing brush member 10 which is slidable horizontally on guide rails 14 and 14' back and forth between an end frame b of the main body A and a stopper wall 17 positioned above the dust collecting compartment 19. The first dust collecting member 10 has numerous inclined short bristles 12. The guide rails 14 and 14 are connected to and extend along the opposite side walls of the inner frame 0 (see FIG. 3). Provided below the first dust removing member 10 is a secondary dust removing stationary brush member 1 l fixed, at its opposite ends, to the opposing side walls of the inner frame c. The second dust removing member 11 is provided at its face with numerous inclined bristles 13 engageable with the bristles 12 on the first dust removing member 10. The bristles l2 and 13 are inclined in the same direction, i.e., to the left, as are the bristles 8 on the second roller brush 7. In contact with the upper face of the first dust removing member 10, there is provided a cushioning plate 15 within which is arranged an elastic sponge or like sheet material 16. This plate 15 with elastic sheet 16 is interposed between the main body cover 18 and first dust removing member 10, so as to make it possible to elastically automatically adjust the sliding relation of the first dust removing member 10 with respect to the second roller brush 7 and also relative to the second dust removing stationary member 11.

Indicated with 21 is a handle which is pivotable around a connecting pin 20 by the operator.

When the sweeper explained above is advanced (first forward movement) on a carpet in the direction of the solid arrow by pushing the handle 21 forwardly, the drive wheels 1 and 1' rotate in the opposite direction, causing the driven wheel 3 to rotate the first bristle roller brush 5 in the direction of the movement of the sweeper or main body A. Consequently, relatively coarse dust on the carpet is forced up by the bristles 6 :of the first roller brush 5 and thrown into the dust collecting compartment 19' as already known.

On the other hand, the second roller brush 7 rotates in the counter-clockwise direction at a reduced speed, while pushing the first dust removing slider member 10 toward the stopper wall 17 by the frictional contact between bristles 8 and 12. Since the bristles 8 on the outer peripheral surface of the second roller brush 7 are inclined in the counter-clockwise direction, the bristle 8 merely slide along the surface of the carpet in a slipping manner when the main body A travels in the direction of the solid arrow. Accordingly, the first roller brush 5 alone performs cleaning during the first forward movement of the sweeper or when the main body A moved forward direction of the solid arrow shown in FIG. 1.

If the main body A is subsequently drawn by the handle 21 backwardly or in the direction of dotted arrow of FIG. 1 (first backward movement of the sweeper), the drive wheels 1 and 1' rotate in the direction opposite to that of the dotted arrow, permitting the first roller brush 5 to sweep up relatively coarse dust from the surface of the carpet into the dust collecting compartment 19 with its bristles 6 while being driven by the driven wheel 3 in the direction of the dotted arrow. On the other hand, the second roller brush 7 rotates in the clockwise direction or in the direction opposite to that of the dotted arrow, namely opposite to the direction of advance of the main body A. However, due to the friction or engagement between the first roller brush 7 and the first dust removing member'll) which has been brought to a halt by its abutment against the stop wall 17 by the preceding forward travel of the main body A, the speed of rotation of the first roller brush 7 is reduced. Thus the fluff, lint or fine dust which has been left on the carpet without being removed by the bristles 6 of the first roller brush 5 is swept off and taken in and among the inclined bristles 8 while the second brush 7 is rotating in the clockwise direction as if being dragged on the carpet. With this clockwise rotation of the second roller brush 7 first dust removing member 10 is pushed backwardly due to the engagement with the brush 7 until it is stopped by the end frame b. As the second roller brush 7 further rotates, the fluff, lint or fine dust caught among the group of inclined bristles 8 is raked off and taken up by the bristles 12 on the face of the first dust removing member 10 (now stationary due to engagement with the frame b) as if by combing, this rendering the bristles 8 on the second roller brush 7 clean and ready for the subsequent brushing operation.

When the main body A is again pushed forward in the direction of the solid arrow (second forward movement of the sweeper), the first roller brush 5 sweeps relatively coarse dust and the like from the carpet into the dust collecting compartment 19' as already described with respect to the first forward movement of the sweeper, while the second roller brush 7 rotates at a reduced speed while simply sliding on the carpet in a slip ping fashion. At this time, the first dust removing member 10 is advanced to the position of the stop wall 17 due to the frictional engagement with the roller brush 7 and is then stopped as it abuts the stop wall 17. Since the bristles 12 on the under face of the first dust removing member 10 are inclined in the same direction as the bristles 13 on the upper face of the secondary dust re- 7 without being combed off by the bristles 13, although the bristles 12 and 13 are in contact with each other during this forward movement of the member 10.

If the main body A is drawn again in the direction of the dotted arrow for backward movement (second backward movement of the sweeper), the first roller brush again sweeps up relatively coarse dust from the carpet into the dust collecting compartment 19. While the second roller brush 7 takes up fluff, lint or fine dust from the carpet into the bristles 8, the first dust removing member moves backward in contact with the brush 7 stops at the position of the end frame b, thereby permitting the bristles 12 on the first dust removing member 10 to take off the dust and the like retained in the bristles 8 by combing as already described. During the backward travel of the first dust removing member 10, the dust and the like caught among the bristles 12 during the preceding backward travel are scraped off by and transferred into the bristles 13 on the secondary dust removing stationary member 11 by combing by virtue of the engagement between the bristles 12 and 13. The dust and the like thus lodged among bristles 13 are then pushed forward by the subsequent forward movement of the first dust removing member 10, and eventually discharged into the dust collecting compartment l9 automatically. Every time the said forward and backward movement is repeated, the bristles 6 on the first roller brush 5 sweep relatively coarse dust from the surface of the carpet into 19 and 19 respectively, whereas the second roller brush 7 takes up fluff, lint or relatively fine dust remaining on the carpet only during the backward movement. The dust or the like taken up by the second roller brush 7 is then raked off from the bristles 8 and transferred to the bristles 12 on the first dust collecting member 10 which is in sliding contact with the bristles 8. The dust or the like taken up by the bristles 12 is thereafter transferred to the bristles 13 on the secondary dust removing stationary member 11 during the subsequent backward movement of the sweeper. During the following forward movement of the sweeper, the dust or the like retained among the bristles 13 is progressively pushed out by the bristles 12 and finally discharged into the dust collecting compartment 19 automatically.

In this way the carpet sweeper according to this invention disposes of relatively coarse dust by utilizing the characteristics of the conventional bristle roller brush. At the same time, fluff, lint or relatively fine dust adhered to the pile surface of carpet which can not be removed by the conventional type of bristle roller brush 5 is caught by the inclined bristles 8 on the second roller brush 7 and is ultimately pushed into the dust collecting compartment automatically. Thus the drawback of the conventional carpet sweepers can be eliminated.

In the case where the handle 21 in the embodiment FIG. 1 is shifted to the position indicated in the dotted line, the position of the first roller brush 5 relative to the second roller brush 7 will be reversed. If the handle 21 in this position is pushed to advance the main body A in the direction of the dotted arrow, the first roller brush 5 will achieve exactlythe same result as explained before. However, the operation and effect of the second roller brush 7 will be exactly the reverse of the above description. Thus, the cleaning operation is conducted only during the forward movement of the sweeper. More specifically, the advance of the main body A in the direction of dotted arrow rotates the second roller brush 7 at a reduced speed as if being dragged on the carpet due to the friction with the first dust removing member 10. Since-the bristles 8 lean toward the dotted arrow, namely in the counterclockwise direction, they pick up fluff, lint or relatively fine dust. Because the bristles 12 on the first dust removing member 10 and the bristles 13 on the second dust removing stationary member 11 lean in the same direction as bristles 8 (as mentioned before), the dust or the like caught among the bristles 8 is thereafter progressively transferred therefrom to the bristle group 12,

then to the bristle group 13 by the cooperation therebetween as described before and is finally pushed automatically into the dust collecting compartment 19, whereby the carpet will be completely cleaned.

Another embodiment of this invention is illustrated in FIG. 2 wherein two sets of second roller brushes and associated members are provided in front of and to the rear of the first roller brush 5. Thus there are provided first dust removing members 10, 1t), cushioning plates 15, 15', secondary dust removing stationary members 11 and 11' and stopper walls 17, 17 in combination with the respective second roller brushes 7 and 7'. The inclination of the bristles 8, 12, 13 is opposite to that of the bristles 8, 12, 13. As will be apparent from the description of the embodiment shown in FIG. 1 the first roller brush 5 in this embodiment sweeps relatively coarse dust from the surface of the carpet into a dust collectingcompartment 19' or 19 every time the main body A moves forward (in the direction of solid arrow) or backward (in the direction of dotted arrow). Fluff, lint or relatively fine dust on the carpet is picked up by the bristles 8' of the second roller brush 7' during the forward movement or by the bristles 8 of the second roller brush 7 during the backward movement. Due to the cooperative contact between the bristles 12' on the first dust removing member 10' and the corresponding bristles 13 on the secondary dust removing stationary member 11', or between the bristles 12 and 13, the dust caught in the bristles 8 is transferred therefrom to the bristles 12' and then to the bristles 13' while the dust in the bristles 8 is transferred therefrom to the bristles 12 and then to 13 progressively by raking and is eventually pushed into the dust collecting compartment 19' or 19 as already described. The second roller brushes 7 and 7 in this embodiment can clean during forward and backward movements respectively. Therefore, cleaning can be effected by the first roller brush and second roller brushes every time the main body A is moved forward and backward.

Still another embodiment of this invention is shown in FIG. 4. This embodiment is substantially same as that shown in FIGS. 1 and 3 except that the direction of inclination of the bristles on the second roller brush is opposite to that shown in FIG. 1 and that the arrangement of the first and second dust removing members is some what modified. Thus the second roller brush 7 have bristles 8 included in the clockwise direction is rotatably supported by a shaft 9 on the inner frame c. Positioned above the dust collecting compartment 19 and in contact with the second roller brush 7 is an arcuate first dust removing member 10 rotatably supported on the inner frame c by a shaft 22. Above the first dust removing member 110 and engageable therewith is a correspondingly arcuate secondary dust removing stationary member ll fixed at its opposite side ends to the inner frame c. Bristles l2 and 13 provided on the outer face of the first dust removing member if) and on the inner face of the secondary dust removing stationary member 11 respectively lean in the same direction (as seen at the respective contacting points) as the bristles 8 on the second roller brush 7. To properly regulate the amplitude of or to stop the rotation of the first dust removing member lltl, stopper projections 23, 23 and 25, 25 are provided on the opposite sides of the inner frame c respectively. An elastic member 2 such as sponge sheet may be provided within the first dust removing member it).

When the main body A of this embodiment is advanced in the direction of the solid arrow by pushing the handle 21', the bristles 6 of the first roller brush sweep relatively coarse dust from the surface of carpet into the dust collecting compartment 19' as already described. The second roller brush 7 in this case is slowed down by the frictional contact with the first dust removing member and advances as if being dragged on the carpet while rotating in the direction of the solid K arrow (counterclockwise direction), namely in the direction opposite to the direction of advance of the main body A to sweep up fluff, lint or relatively fine dust from the surface of the carpet and retain the same among the bristles 8. The dust or the like thus removed by the bristles 8 is raked off and transferred to the bristles 12 on the first dust removing member lltl (now in stationary position due to engagement with the stopper a by combing action. Subsequently, if the main body A is drawn in the direction of dotted arrow, the second roller brush 7 rotates in the clockwise direction opposite to that of the dotted arrow while being slowed down by the friction with the first dust removing member 10, so that the brush 7 smoothly slides along the carpet surface. During this movement, the first dust removing member 10 is pushed up toward the stopper projections 23. When the main body A is advanced again in the direction of the solid arrow, the second roller seal brush 7 again picks up dust or the like from the carpet by the bristles 8 in the same manner as during the previous forward movement, while pushing the first dust removing member lltl down to the stopper pr0jections 25. At this time, the dust and the like among the bristles 12 on the first dust removing member it) is raked off by a combing action and caught among the bristles E3 on the secondary dust removing stationary member ll. On the other hand, the dust taken up by the bristles 8 is raked off by the bristles l2 by a combing action. When the main body A is then again drawn in the direction of the dotted arrow, the second roller brush 7 acts in the same manner as in the case of the previous backward movement, forcing the first dust removing member 10 toward the stopper projections 23. The main body A, when advanced again in the direction of the solid arrow, will perform the same operation as in the preceding forward movement. Particularly in this case, the dust or the like in the bristles E3 on the secondary dust removing stationary member 111 is forced out by the bristles l2 and is finally discharged into the dust collecting compartment l9 automatically.

ltl

Through the repetition of the forward and backward movement described, relatively coarse dust on the carpet is removed by the first roller brush, while fluff, lint or relatively fine dust is picked up by the bristles 8 on the second roller brush 7, transferred to the bristles 12 on the first dust removing member l0 and then to the bristles B on the secondary dust removing stationary member 1111. Thus eventually, the dusts will be collected in the dust collecting compartment 19 automatically.

Further it will be of course apparent that the second roller brush constructed according to this embodiment may be provided in front of and to the rear of the first roller brush symmetrically thereof.

What we claim is:

l. A rotary type sweeper, comprising: a housing body; a first conventional roller brush mounted within said housing body and being rotatable in engagement with the surface to be cleaned when the sweeper is moved forwardly and backwardly; dust collecting compartments disposed in front of and to the rear of said first roller brush; a second roller brush rotatably mounted within said housing body adjacent said first roller brush, said second roller brush having short bristles closely implanted on the surface and inclined in the same direction along the circumference thereof; a first dust removing member having short bristles closely implanted on the surface and inclined in the same direction and being positioned adjacent and movable in engagement with said second roller brush; a second stationary, dust removing member positioned within said housing body adjacent said first dust removing member, said second dust removing member having short bristles closely implanted on the surface and inclined in the same direction, the bristles on said first dust removing member being engageable with the bristles on the second dust removing member, and the bristles on said second roller brush, first dust removing member and second dust removing member all being inclined in the same direction.

2. A rotary type sweeper as claimed in claim 1 wherein the first dust removing member is in the form of a flat brush which is horizontally slidable, when engaged with the rotating second roller brush, toward or away from the second stationary dust removing member depending upon the direction of the rotation of the second roller brush.

3. A rotary type sweeper as claimed in claim 1 wherein the first dust removing member is in the form of an arcuate brush which is swingable, when engaged with the rotating second roller brush, toward or away from the second stationary dust removing member which is correspondingly arcuate, depending upon the direction of the rotation of the second roller brush.

4. A rotary type sweeper as claimed in claim 2 further comprising a stopper means to stop the movement of the first dust removing member.

5. A rotary type sweeper as claimed in claim 1 further comprising a third roller brush similar to'said second roller brush, and first and second. dust removing members, said first roller brush being arranged between the second and third roller brushes, the bristles on the third brush being inclined in the direction opposite to that of the bristles on the second brush.

=-l l =l= 

1. A rotary type sweeper, comprising: a housing body; a first conventional roller brush mounted within said housing body and being rotatable in engagement with the surface to be cleaned when the sweeper is moved forwardly and backwardly; dust collecting compartments disposed in front of and to the rear of said first roller brush; a second roller brush rotatably mounted within said housing body adjacent said first roller brush, said second roller brush having short bristles closely implanted on the surface and inclined in the same direction along the circumference thereof; a first dust removing member having short bristles closely implanted on the surface and inclined in the same direction and being positioned adjacent and movable in engagement with said second roller brush; a second stationary, dust removing member positioned within said housing body adjacent said first dust removing member, said second dust removing member having short bristles closely implanted on the surface and inclined in the same direction, the bristles on said first dust removing member being engageable with the bristles on the second dust removing member, and the bristles on said second roller brush, first dust removing member and second dust removing member all being inclined in the same direction.
 2. A rotary type sweeper as claimed in claim 1 wherein the first dust removing member is in the form of a flat brush which is horizontally slidable, when engaged with the rotating second roller brush, toward or away from the second stationary dust removing member depending upon the direction of the rotation of the second roller brush.
 3. A rotary type sweeper as claimed in claim 1 wherein the first dust removing member is in the form of an arcuate brush which is swingable, when engaged with the rotating second roller brush, toward or away from the second stationary dust removing member which is correspondingly arcuate, depending upon the direction of the rotation of the second roller brush.
 4. A rotary type sweeper as claimed in claim 2 further comprising a stopper means to stop the movement of the first dust removing member.
 5. A rotary type sweeper as claimed in claim 1 further coMprising a third roller brush similar to said second roller brush, and first and second dust removing members, said first roller brush being arranged between the second and third roller brushes, the bristles on the third brush being inclined in the direction opposite to that of the bristles on the second brush. 